Lubrication system for sewing machines



May 13, 1952 G. sAuER ETAL 2,596,728

LUBRICATION SYSTEM FOR SEWING MACHINES Filed Dec. 2, 1949 6 Sheets-Sheet l ATTOR NE Y.

May 13, 1952 G. sAUER ErAL LUBRIcATIoN SYSTEM FOR sEwING MAcHINEs Filed Dec. 2, I1949 6 SheetS-Sheet 2 INVENTORS. GEORGE sAuER cLARENcE c. srwTH ATTORNEY.

6 Sheets-Sheet 3 FIG-3 GySAUER ET AL LUBRICATION SYSTEM FOR sEwING MACHINES .\\u u E? IQ v En: /3

F IG. 4

May 13, 1952 Filed Dec. 2, 1949 -CLARENCE C. SMITH ATTORNEY.

May 13, 1952 G. sAUER .I-:rAL I LUBRICATION SYSTEM F OR SEWING MACHINE-S 76 sheets-sneet 4 Filed Dec. 2, 1949 8 INVENToRs.

GEORGE 'SAUER CLARENCE C. SM|TH Egg:-

ATTORNE Y.

May 13, 1952 G. sAuER ETAL 2,596,728

LUBRICATION SYSTEM FOR SEWING MASHINES Filed Dec. 2, 1949 6 Sheets-Sheet 5 BZ IN V EN TORS.

GEORGE SAUER CLARENCE C. SMITH ATTORNEY.

G. sAUER l-:TAL

LUBRICATION SYSTEM FOR SEWING MACHINES May 13, 1952 6 sheets-sheet 6 Filed Dec. 2, 1949 INVENTORS. GEORGE SUER CLRENCE C: SMITH ATTORNE Y.

substan-ces, and-other-foreign matter Which it has Patented May 13, 1952 UNITED.- s'r-Ares vrv ort-ICE LUBRICATION SYSTEM FOR SEWING- MACHINES George Sauer, Berwyn, and Clarence C. Smith,

Chicagfiuallvl., asflsignorsv to Union Special Machine Company? Chicago, Ill., a corporation ofvv Illinois ApplicationDecember 2, 1949,-SerialNo. 1 301 1'54 Thiseinvention relates. to Sen/fine. machinee and. more *particul-ar1y toj cyclic] IubrioatiOn systems providedV in such machnes intended for high sp'eedoperationson, therorder of 4,009 to 5,000

stitches-per minute, or more.

Sewing ma-chines have heretQfQre been provided k with'enclosed housings .adaptedfto retain, ina substantially lubricant. .tight chambery or charnbers, the principal Operating devices of the machinev.v Hovvever, 'certainbfthe moving parts, suoh." asV certain. of. the stitch-forming instrumentalitiesandthe Workfeeding devices, must be provided'routside of .the enclosed housing where theyfimay'coope'rate.properIy With the Work to be stitched. i Adequate lubrication of. these .moving parts,4 Voutside of. the enclosed housing, presents afmore. dificult problem. Various means have been-suggested, forv supplying lubricant to these.

parts =frc'Jmthe mainreservoir Within the housing.v Htqvvever,it.y is difficult, if -not impossible, to supply relativelfyfsliding suriaces and, therefore, a certain eoessfmust beprovidedwhich then drips from thesurfac'es beinglubricatedf To avoidwaste of.

the' lubricanttheexcess has heretofore been colleoted ,-in someemachines, in a bottle orother cont inerattached to the base of vthe machine at ai-suitable lpoint and When. the .bottle has become filleditjhas been Vdetached i and replacedby anotherfbottle and -the'collected lubricant .has

been subjetedito a filtering or other..refining-- operation-ton reclaim it.- It .Will be .appreciated.

that'sulchexpess lubri-cantfdripping from the stith-formingand Work-feeding; devices y.becomes T cqntaminated With lint and the filler substances used in most fabrics being stitched. Beforereusing .fthelcollected excess lubricant itis, therefore,-necessarytoremove from -it the'lint, filler aoeumul'ated:inhuse. This prior method of dealing v With-e the problem has beenflreasonably. satis-H factory, g-but;V it -has the Vobjection that the iman. reservoir'vvithin-the machine becomes depleted of 19 annasf (oi. 112-256) 20 just'enoughllubricant to meet the.. needs .ofthe 2 of thel excesslubrioant in asumpand the return of this, by'l gravity, -to the' reservoir :Within the main -encl'osed housing. Filt'erin'g 'm'e'ans hassometimesbeen i pr 1 Vi-ded between the' sump 'and the main reservoirjtlo' 'removelintand other "-solid particles.l Hovvever, "this arrangement vhas no't proved satisfaotorv due yto the 'fa'ct'that theffiltering means has-'very qu'iklynbecome 'logge'd With thehforeilgn matter and the return of* further lubri ant. to the nain'lres'ervoiif has been -prevented or" reduced to such'a slo'wfratethat 'an objectignably', .large amount hasH accum'ulated -in the sump, even yto the point of overflowing'from ,the .1a tter, Moreover, the supply in the main reseryoir hasubeen reduced to an objectiqnahly'low point.

A primary* objet of the, present invention has been to. evereome, .the Obeetieneltejjthe' Sehe'mes heretefere empleyed eheteerevidee Cyclieieys; te'm in Which lubricant is supplied from a reser! voirin a main enlosed housingJ- to parts exterior.

end, eeetive. pumping-h2eeh1? bliififludesi in the. system, in such a Wayvasto draw the ezcess lubrieem. through. the.. .fihelcineneen eh'd. force it positively into*themainreservoir r Ithasbeen ing unit may be used. continuouslvjover a relatively. 1one. .p-eriod. j0f..ytif.1f1e.y ef're it becomes' clogged.. 'to the, pointthat .thefsystem :fails to func-- tion Yproperly; The pumping'me'ans, if properly;

- -construoted and arranged, has y.been .found ;t o

its-lubricanti ordrops toea'dangerously low level,

before -y-this 4conditionh is4 observed.I As Va. result,

expensive bearingsI become VVoverheated .and -are 1 damaged. A1so,-it has frequently happened that the bottle orfother container into .Which the. ex.- cess'f-lubricant isldirected V.becomes .filled more 2 quikly; than expectedv by the operator and the,

excessthen-spills over onto the floor or intothe operator's-lap. i

In an effort to overcome the drawbacks of the above; :described arrangement, provisions have been made, in some instances, for the collection tion end-.yet hrevideyelhple 'ene createthe veift'ofnahead of lubricafit;equivalent1 to a number of inches, above the filtelfngf f and. this .is adequate to i carryvtlfifie i lubriant through .therfilterlflgr means a-t a Sufi'iqntly rapid provide-e; eimp1e..but1.emsieet form. of.-e1mlieine means, in a system ofthe'above indieated char-lf a.cter,,which Will require littlepo er I to'dravv theing the pumpins means, t a .mererargidegulaf speestnan .tnatynthedm shares; the niaeh'in.

As a specia1,, feature of thm plfiasev of theinv'eii'I tion, it has been found particularly eiectivetov Irfv some and inexpensive construction and may be applied-H to a sewing machine of the character indicated Without the necessity of fine tolerances in. the relationship between certainof the parts.

Still another specific object of theinvention has been to provide a readily replaceable filtering unit, for the purposes specified, Which is so simple and inexpensive that it may be discarded after it has become clogged With lint and other solid particles, and readily replaced by a fresh unit of the same character. v I

*Other objects, features, and advantages of the invention-will appear from the following detailed description of several embodiments thereof which will now be given in conjunctionv with the accompanying drawings, in which:

Fig. 1 is a vertical sectional view taken longitudinally through an overedge type of sewingv machine embodying the invention;

.Pig- 2 is a horizontal sectional view through the machine, taken along the line 2-2 of Fig. 1;

Fig- 3 is a transverse vertical sectional view through the machine, taken along the line 3-3 ofEisl; i V

fijis a detail view showing a portion of the oil collecting sump and the filtering means mounted therein;

;Fig.;5 is a view, partly in front elevation and partl-ynhin vertical section, through a fiat bed machineembodying a modified form of the invention; I

Fig; 6 is an enlarged detail view, in vertical section, showing the filtering and pumping means employed in the machine of Fig. 5 as assembled on a-portion of the latter;

Fig. 'Tis an exploded perspective view of the several parts forming the flltering unit of Fig. 6;

Fig; 8 is an exploded perspective view of the pumping means shown in Fig. 6;

Fig. 9 is a top plan view of an element of the pump assembly shown in Fig. -8;

Fig. 10 is a detail view inV vertical section through the central portion of the element of Fs. 9; V

Fig.V 11 is a detail view, in vertical section, showing a modifled arrangement for driving the pumping means;

Fig. 12 is an exploded perspective view of the parts of a modified form of filtering unit;

Fia. 13 i: an assembled perspective view of the modifled filtering unit of Fig. 12: and

Fig. 14 is a vertical sectional view through the filtering unit of Fig. 13 as it is assembled in the bottom of the sewing machine frame.

Turning now to Figs. 1 to 3 inclusive of the drawings, the invention is shown applied to an overedge sewing machine of the type disclosed in'the Peterson et al. application, Serial No. 122,204, filed October 19, 1949. For full details as'to the construction and operation of this machine reference may be had to said pending application.V The machine will be described only generally here. It comprises a main frame having a vertical wall structure [0, a bottom plate ll, and a removable cover [2 forming an oiltight housing serving to enclose the principal operating parts of the machine and adapted to retain a body of lubricant [3 in a reservoir provided at its bottom. A laterally extending portion [4 at the left end of the vertical wall Vstructure [0 (Fig. 1), is disposed beneath the stitch forming and work feeding devices of the machine, to be briefly described hereinafter, and provides a shallow sump [5 beneath these devices. This extension is also arranged to provide a support for various parts exterior-.iof 'them'ain enclosed housing of the machine, including certain pivotally mounted parts, suchas a Vwork supporting member [Sa and a cover .[56 forr partially enclosing certain of the work feeding devices. The arrangement is such that access is readily provided to the devices exterior of the main enclosed housing, for adjustment, repair,l cleaning purposes, and the like.

The machine is provided with a main driving shaft [6 which. extends 'longitudinally through the main enclosed housing of the frame and projects from the latte'r at Vits right end (Fig. 1)' to which is Secured a combined hand wheel and pulley [1 through which the machine may be driven. Shaft [B also extends through the left wall of theenclosed housing (Fig. 1) in which it is journaled. The projecting endof the shaft, as will be explained. carries means for Operating the work feeding devices of the machine.

The stitch-forming devices include a curved needle [8, a reciprocatory under looper [9, and

a reciprocatory and oscillatory overedge looper 20. 'As explained in said pending Peterson et al. application, either of vthe loopers may be replaced by a spreaderto form a .two-thread stitch in lieu of a three-thread stitch. Curved needle [8 is carried by an arm 2l secured to a rock shaft 22 (Fig. 2) Which 'extends through the .left hand vertical wall of the J enclosed housing into the interior of the latter. Here there vis Secured to it a clamping member 23 which is connected by i a pitman 24 with an eccentrickor crank portion of the shaft [6 through which a desired rocking movement is imparted to the shaft 22. Under looper [9 is carried by a reciprocating rod 25 extending through the left vertical wall of the enclosed housing into the interior of the latter. It is reciprocated by means of a link 26 which is pivotally connected at one end to a block 21, secured to the rod, and at its opposite end to the lower end of an arm 28 extending downwardly from asleeve rockably mounted on a shaft 29. A laterally extending ball pin 30, carried by the sleeve, is connected by a pitman 3[ with a spherical eccentric or crank portion 32 of the main shaft [6.

Overedge looper or spreader 2!! is carried by a rod 33 which also extends into the interior of the enclosed housing through a hearing in the left-hand vertical wall of the latter. 'This rod is arranged to be given both a reciprocatory and oscillatorv movement. For reciprocating the rod, a block 34 is mounted thereon between a pair of collars secured to the rod. Vthe arrangement being such that the rod vmav be oscillated Within the block, but will he reciprocated upon axial movements of the block. Such movements are imparted by means of a link 35, pivotallv connected at one end to the block and pivotally connected at its opposite end to the lower end of an arm 36 freely carried hv the shaft 29. A link 21. pivotally connected with the arm 36 at an intermediate point. forms one arm of a toggle, the other arm 38 of which is rockably mcunted 7. insurefan', effective pumping action. It-is lmportant that the pump formed by the spirally grooved portion of the shaft and its bearing sleeve should be capable not only of pumping the maximum amount of lubricant delivered to the sump l but it must also be capable of creating air suction so as to assist in drawing lubricant through the ltering means under a suitable head. i

'At an intermediate point the shaft 15 is journaled in a bushing 18y carried by a vertically extending wall within the housing. Collars .11, secured to the shaft at opposite sides of the bushing Y18, serve to take the 'axial thrusts of the shaft and maintain the latter in the desired axial position. At its extreme right end, the shaft has-Secured thereto a hub 19 of an imamma,

peller 80. The latter is supported by the shaft within the oil distributing member 59 and has only a small clearance at its lowermost'pointin relation to the flange 62 of member 59./ Impeller 80, as best shown in Fig. 3, is formed with a disc-like portion Bl and a series of fianges or projections 82 which extend radially from the hub and in an axial direction from the face of the disc 8l. A series of pockets 83 is thus provided parallel with and adjacent to the inner face of the disc-like portion of member 59. These pockets are open at their outer, larger ends.

Upon rotation of the main shaft [5 of the machine, the member 59 will be revolved at the same angular speed and will create a moving band of lubricant around the inner periphery of the'flange 62. This band of lubricant will be carried around at substantially the same circumferential speed as the flange 82. As the revolving llubricant strikes the flanges 82 and enters the pockets 83, it Will serve to effect a fluid drive connection between members 59 and 80. Due 'to the difference in the relative diameters of these members,- the member 80 will be rotated at a substantially higher angular speed than member 59. In the construction illustrated member' 80, and hence shaft 15, will be rotated at about 3 times the angular speed of the main shaft IS. This will cause the spiral groove pump 16 to create a substantial pumping action and air-Suction. It has been found more than adequate to draw the lubricant from the sump IS as rapidly as the excess lubricant accumulates therein. This pumping actionis effective for this purpose for a substantial period of time, in spite 'of the accumulation of foreign matter on and in the filtering means. When this accumulationreaches the point at which it retards too much the flow of .lubricant through the filtering means, the latter may readily be removed for cleaning and then replaced, or a new filter and screen unit may be substituted. It is simply necessary to remove the screws 'H to permit such replacement. v

Turning now to Figs.,5 to 10 inclusive, there is shown an adaptation of the invention to a fiat bed machine of the type disclosed in the Peterson et al. application Ser. No. 58,222, filed November 14, 1948. This machine has a frame providing a base portion 84 with a |work supporting surface 85, a vertical standard 86 rising from one end of the .base and an overhanging arm .81 extending laterally from the vertical standard over the base and terminating in, a'

needle head 88. A rotary drive shaft 89 is provided in the base, this being journaled in suitable bearings in a wall 90 at the left end of the frame (Fig. 5), in a plurality of intermediate walls SI. and 92, and in an'outer wall 93, at the right-hand end of'the frame; the shaft which projects outwardly from. the frame, there is secured a combined handwheel and'pull'y 94 through which power may be supplied'for 'driving the machine. A

A needle bar L95 is mounted for vertical reciprocation in the needle head .and carries a plurality of needles "'at its lower end.. Recipro-V cationof theneedle bar is eifected through connection with one end of a leverV 91, Vthe oppositeconnections from the shaft 89 serve to rock the.

member |02 to impart needle avoid Vmovements to the looper. Connections are also provided from themain shaft for s-winging the carrier |0| about its pivot to impart loop seizing and shedding movements to the looper.V These latter connections include a pitman |03 having ball pin connections with an intermediate point on the carrier and with the upper end of an arm IM. Suitable work feeding devices are included in the machine, these being, in part, shown at lfl. The feed stroke and return movements are imparted to the feed dogs (not shown) by an eccentric at the outer end of the shaft189 cooperating With a link m6. For further details asy to the construction and operation of the stitch-forming and work feeding devices of the machine, reference may be had to said Peterson et al. application Serial No. 58,222.

An enclosed oil reservoir is provided within the frame between the walls 9l and 92 and between the latter and the outer wall 93. Of course the front and rear walls and the top and bottom members of the frame complete the enclosure of the reservoir. In efiect, there is but a single reservoir which is divided into two parts by the Wall 92; the parts are inter-connected by an opening, or series of openings, 101 near the bottom of the frame for the free passage of lubricant through the wall 92. Lubrication of the parts in the vertical standard and overhanging arm is eifected by spray generated within this of oil from the reservoir within the enclosed, -housing through various channels in the frame and suitable wicking. Thus, oil is delivered from the reservoir through openngs l08 (Fig. 6) in a portion of the wall 91, these openings leading to a vertical passage 109 in the wall. Passage |09 is connectedL by a transverse passage H0 with various other channels in the base, including horizontal, transversely extending passages HI (Fig. 5) near the left end of the base and vertical passages H2 communicating with the passages lll. Suitable wicking H3, receiving lubricant from within one or another of the various passages, serves to deliver the lubricant. to the surfaces of the loop-taking and work-feeding mechanism requiring lubrication. The ballpin connection between the pitman I03 and arm [04 may be lubricated by. wicking Ila extending through a tube which communicates with the interior of the enclosed housing and receives lubricant directly from the mist therein and car- On the end 'of I .may be forced by the plug H5.

ries this lubricant to a-point in the path of movement -of vthe connectionmentioned. It will be understoodthat other passages and wicking and the like may be provided to supply lubricant to all of? the parts in the base outside ofthe enclosed housing which require lubrication. Reference may be had to said Peterson et al; application, Serial' No. 58,222 for additional details 'as Sto, the lubricant distribution system.

Excess lubricant delivered 'to theV various exterior partsin the base will drip therefrom and be collected ina sump IM which 'is suitablypositioned.V and shaped to catch the excess from all points. At a low point in the sump an opening j'of suitable size is provided, this being largely -closed by a plug II (Figsy and 6) having Va pressed fit in relation to the walls of the opening. The opening' is preferably of larger diameter at 'its lower 'end than at its topv and thus lceivethe screws. Through the center of the plug an axially extending opening I IB is provided, this being of relatively small diameter at yits lupper end and yincreasing in diameter in several steps -toward its lower endto provide suitable,v shoul- 'ders. A'screw plug II9 cooperates with threads formed in the wall of the opening, at its lower end, to effect a lubricant tight'closure. Above the screw plug 'a spring I20. is mounted, this spring'serving to retain filtering means, comprising a' pad- I2I formed of felt or the like and .a screen or perforated plate I22. These areforced by the spring against a shoulder providedby the reduced diameter of the opening IIS at its vupper end. I

Spring I20 lis within a lubricant a-receiving pocket between the filtering means and the top of the -screw plug IIS. This pocket communicates, through a radial passage I2-3 extending through the enlarged portion of the plug H5, with a tube I21l. The Vlatter may be formed-of any suitablev materiaLsuchas copper, brass, or an appropriate plastic. At its opposite end, the tube i-is'inserted in a radialpassage I25 inan enlargdhead portion of.v ay bearingsleeve I26. The'latter has a pressed fit engagement with an opening'through the bottomvof the reservoir of the enclosed housing. f. Tube I24 is received by a groove or'recess I21, formedl by milling orthe liker-in the bottom of the frame. To effect. an oiltight-:seal vbetween the bearing sleeve I26 and the bottom of the reservoir a gasket I28 maybe provided,.this being squeezed by vthe enlarged head of the .hearing sleeve againsta shoulder formed by the reducedporti'on'of thepening through theL bottom of the reservoir. 'I-Iolesv I 29 extendin'g through the enlargedheadof the bearing ysleeve are adapted to receive machine screws (not shown) for securing the'sleeve to the frame. Gasket I28 is provided with suitable holes to 'Ire- 'ce'ilve the screws and the 'coop'e'rating shoulder at the bottom offthe reservoir is fprovidedwth threaded holes to receive the ends of the screws.

Tof-inure 'a lubricant tight vconnection between'the tube I24 and the plugv ll5'and hearing sleeve I26, 'it has Vbeen found desirable to assemble these three vparts vseparately and then apply'them'" as a unit' to the machine frame. To

i I3I forclosing 'theJbottom of the jrecess.

.larger vertical" passage I39. municates with 'flan axially'v extending. .bore Mil Nio avoid undulyfine toler'ances in the relative po- "sition of 'the openings which receive the .plug

'sirable to provide the tube 124 with a slight bend and to form this of flexible material, so that the tube maybe bent to a greater or lesser extent to permit kthe plug and bearing sleeve to vbe inserted freely in their openings. Groove or recess I21 in the bottom of 'the frame'should be of sufiicient width to'accominodate'the bend in thetube.

A' recess is provided in the lower end of the bearing sleeve I26, centrally thereof, and this. recessis screw threaded to receive a threaded plug Plug 'I3I has a reduced shankportion I32 Whichy extends upwardly into the recess, but leaves an 'annular'pocket around the same which communicate's' With the' radial passage |25. vAbove the recess I30, the hearing sleeve is provided with an axial bore of smaller'diameter to receive a .spirally grooved shaft I33. The lower end of this shaft is vcarried by the top'cf lthe shank I 32 of the screw plug which may 'besuitably adjusted to hold the shaft at'the desired elevation. At its upper end, the shaft I33 carries a bevelgear .I34 which is Secured to the shaft by a screw I35. Bevel gear I 34 meshesV with another bevel gear I Secured to the main drive shaft 89. Accord- 'ingly, it will be apparent that upon operation'o'f the machine the spirally grooved shaft I33 will be rotated, the direction 'of rotation being'such as to force any lubricant .in'the' groove upwardly lalong the hearing surface of sleeve p I'26. Bevel gears I and |36 may be'of anydesired relative diameters to cause. the shaft I33 to be drivenat an angular'speedequal to or greater or less than that of'shaft 89. k

Plug II5 is of sufficientisiz'e'to provide-good access to the partsv abovevit, for repair, adjustment and cleaning,when theplug is removed.

yBearing sleeve I26 'is ofjsufiicient outside diameterrtol'permit. the pump unit, including the 'bevel gear I34, toi'be insertedl through the'opening in .the bottom of 'thel reservoir. When removed, italso'iprovides.accessto certain of the devices within' the reservoir. 4

The form and dimensions of the various lubricant passages and I'po'ckets'associated with the V*pumping means, provided byfthe shaft I33, have been' foundftojbe .of considerable importance to lthe proper functioning of thesystem. 'For "examplejit has been found, important to vthe efficient functioning' ofkthe pump that the lubricant be supplied to the spiral gro'ovefthrough'a radial passage [31 (Fig. 6) just'above the' bottom of the bearing's'urface. To 4supply lubricant to this passage a series of radial passages I38, four being shown,v (Figs.. 9 and 10) isiprovided from the exterior surface of the shank I32 to the center thereof. At the center of thev shank the passages I 38 *communicate with ja lsomewhat This, inturn; com- L(Fig. 8) in 'the bottom of'theshaft'I. VRadial passage |3f1 extn'dsfrmthe bore' M0 adlacerlt,

but not quitejat, itsupper end. Passage I3'! imparts a cen'trifugal'pumping action to the lubricant which assists'in creating the'pumping and 'suction' action 'of the.v unit as a whole.v For efficientoperation, it has also been found-desirable to form, the spiral groove in the shaft I33 of 'greater width than 'depth. Excellent results 'have been obtainedfrom the use of a groove having a width of 3/64 .of an inch and having a depth of 1/64 of an inch. It has also been found' desirable t to provide the'groove with a relatively low pitch.

Eight turns to the inch have'been found to produce very effective results. If the helix angle is made smaller, by increasing the number of turns to the inch, the amount of metal left between grooves becomes objectionably small.

However, if eight turns of the spiral are provided per inch in 'a' shaft having an outside diameter of .468

inch, the helix angle is such as to provide good z, results and enough metal is left between succesvsive turns of the groove to afford a good hearing action. If the shaft is of smaller diameter the 'helix angle will increase and the pumping capacity will decrease.

pumping action is made more effective, and the i.. capacity of the pump increased, by having a' groove of greater width than depth. A possible explanation for this is that the greater width of the groove increases the frictional vresistance to the turning of the lubricant with the shaft, since.

it then has a greater surface in contact with the hearing sleeve. By thus retarding the rotation of the lubricant it is advanced more rapidly along the helix as the shaft turns relative to the lubricant.

which contribute materially to the success of the invention. Certain spirally grooved shafts originally employed were found to function in .a

( The foregoing are important considerations spirally groovedshaft l33a, is driven frictionreasonably satisfactory way for a brief interval, p,

but they then become air locked and the system Was rendered inoperative until the machine was stopped and then started again. A total clearance of about .001 of an inch has been found desirable between the outside diameter of the shaft 5 I.

and the inside diameter of the hearing sleeve. However, some variation in this clearance has been found permissible without'substantial variation in the effectiveness of the pump. It has also been found desirable to provide an enlarged re- In tests conducted upon a unit having the form and dimensions set forth above it has been found that with the machine, and also the pump, Operating at 4,000 R. P. M., the pump is capable of delivering 28 ccs. of lubricant per minute. the pump, when so constructed and operated at a speed of 4,000 R. P. M., is capable of creating a suction equivalent to a head of about 4 of oil. This has been found adequate to draw the lubricant through the filtering means substantially as quickly as it accumulates in the sump IM, even after the filter has been used for some time and has become partially plugged with foreign matter. When the filter becomes clogged with foreign particles to such an extent that the system does not operate efliciently, the screw plug H9 may be readily removed and a new pad and screen inserted, or the old pad and screen may be cleaned and reintroduced.

In Fig. ll a modified formof the invention is shown in which the pump, in the form of a It has also been found that ally from the main shaft 89a. For this purpose a friotion disc M2 is secured to the upper end of shaft I33a and this cooperates with the periphery of a friction disc or wheel M3 secured to the main shaft. The relative diameters of the disc M2 and wheel M3 may be v-aried to suit the requirements of the system. In the arrangement shown, the spirally grooved shaft |33a willbe driven at a somewhat slower angular speed than the main shaft. Should it be found necessary or desirable to drive the grooved shaft at a higher speed the diameters of the driving -and driven members may be made equal or the relation between their diameters may be reversed. The pumping action of the system varies substantially directly with the speed of rotation of the grooved shaft.

In Figs. 12, 13 and 14 there is shown a modified form of filteringrmeans which may suitably be made and sold as a unit. It comprises a screw plug M4 which serves the purpose of the screw plug H9, of Fig. 6, but has an upwardly extending portion M5 arranged to receive and extend into the lower open end of a cup-shaped screen member M6. The latter may have a sufficiently tight fit in relation to the portion M5 to be held frictionally thereon, or it may be secured thereto in any other suitable way. Within the screen member M5 there is held a filter lpad M1, formed of felt or the like, this being retained within the member MB by means of a split spring vring M8. The arrangement is such that a small lubricant receiving pocket M9 r is provided between the upper end of projection M5 and the bottom of the filter pad M1. A radially extendingV passage ISO, corresponding with passage |23 of Fig. 6, communicates with pocket M9 throughk the Lvertical wall of the screen member M6. 'It will be understood that the unit to be inserted as a separate assembly may include all of the parts illustrated in Figs. 12 and 13. However, the filtering units to be sold may comprise only the three upper elements of Fig. 12, i.- e., 7the screen member ME, the filter pad I 41 and the retaining ring M8, these being usable interchang'eably on the screw plug M4. v

While several embodiments of the invention have been Vdisclosed in considerable detail, it will be understood that various modifications may be made in each embodiment without departing from the principles and scope of the invention. Features disclosed in connection with one embodiment may be incorporated in another. Thus, the dimensions of the corresponding parts of the pumping means described in connection with Figs. 5 to 10 inclusive, may be followed in the production of the embodiment of Figs. 1 to 4. In all forms of the invention, the spirally grooved member of the pump is preferably formed of Stainless steel or other similar metal which is not subject to corrosionwhen the machine is idle for a substantial period oftime.

What we cl-aim is:

1. In a sewing'machine, a frame having an enclosed vportion providing a lubricant retaining reservoir, a rotary drive shaft extending through said enclosed portion, work feeding devices outside of said reservoir, connections from said shaft for Operating said devices, means for delivering lubricant from said reservoir to said devices in substantial excess of the lubricant consumption thereof, a sump beneath said devices for collectfis to said reservoir, filtering means mount'ed VVa readily accessible portion of said frame for removing solid particles from saidlubric'ant before it is returned to said reservoir, said filtering means being relatively small and of inadequate Vcapacity to handle by gravity said excess: deliveredv tosaid devices, and pum'ping' means operated by rotation of said drive shaft forv drawing lubricant through said filtering means Vand forcinglitinto said reservoir, said pumping means beinguonstructed and arranged to provideia suctionhead on the oil above the filter. i

V 2.; In asewingmachine, a-yrame having-an enclosed portion providing a lubricant; reiainflng reservoir,-a rotary drive shaftextending through said enclosed portion, work feeding devices outside of said reservoir, connectionsfrom said shaft for Operating saiddevices, Vmeans for delivering lubricant, froml said; reservoir to said devices; in substantialexcess of the lubricant consumption Ithereoffa sump beneath said devicesfor-collecting excess lubricant therefrom, 'means prlliding a conduitj-forvreturninglubr-icant from said sump to said 4reservoir, flltering means 'mounted in a vreadily accessible portion of said frame=fon removing solidV particles from said lubrieant-before it'is returned to said reservoir, v'said vfiltering 'means being relatively small and'ofginadequate capacity tohandlel said excess-delivered to said devices, and pumping means comprising-(a bearing sleeve-and a spirallygrooved.y member, within said -sleeveoperated by rotation* of saidy drive 's'haft and arranged to-createjasuction fory drawing lubricantthrough saidfiltering means and forcing it into said reservoir.v I

3. In aa sewing machine, a frame having an enclosed portion providing a lubricant retaining reservoir, a rotary drive shaft extending through said enclosed portion, work feeding devices outside of said reservoir, connections fromsaid shaft for operating said devices, means for delivering lubricant from said reservoir to said devices in substantial excess of the lubricant consumption 4 thereof, -a sump beneathsaid devices for collectingexcess Vlubricant therefrom, means providing a conduit for returning lubricant from said sump to said reservoir, filtering means Vmounted a readily accessible portion of said frame for removing solid particles from said lurbrilcant before it is returned to said reservoir, said filteringmeans being relatively small'and of inadequate capacity to handle said vexeess delii'reredwto 'said devices, and rotary pumping means operated byrotation of said drive shaft and arranged to'create asuction for drawing lubricant through said filtering means and 'forcing it into said reservoir, lsaid pumping means being operatedat higher angular Velocity than said shaft.

-4. In a sewingmachine, a kframe having an enclosed portion -providing a lubricantretaining reservoir, a rotary' drive shaft :extending i through said'enclosed portion, work feeding devices 'outside of said reservoir, connections fromsfai'd' shaft for operating 'said devicesjinea'ns *for1 delivering lubricantffrom said reservoir tosaid 'devices 'in substantial excess of the lubricant consumption thereof, a sump Ioeneathsaid devices forcollecting excess lubricant therefrom, means'pro'viding a conduit for returning lubricant Vfrom 'saidps'iimp tofsaid reservoir, filtering means forfremoving solid "particles from saidy lubrieantfbe'forefit uis returned toisaid reservoir,v Vsaid:filteringmeans being relatively small andv of inadequateV capacity s'ide of'said reservoir, connections from'sai'd i i 'for Operating 'said devices, means for delivering to handleby gravity saidexcess-delivered to said devices pumping means NComp'rising la 'bear-ing sleeve and a 'spirally'grooved rotary'memb'erwwith- Lirl-"said sleeve and'arranged to create afsuction :for drawing lubricant through -said filtering means and forcingitjinto said reservoir, and connections from said drive shaft' for yojgierating vsaid* spirally' groovedmember at higher'afngular jvelocit'y than 'said shaft, s'aid connections comprising hydraulic means operated saidl'sihaft "for imparting motion i' to 'said 'spirally'grooved member through said lubricant. v

5.'In' a sewing machine, al frame Vhavingan f enclosed portion'providing La lubricantjretaining reservoir,' a rotary said' e'nclosed portion, work, feedirig deviefesioutaft drive' shaft extendin'gfthroiigh lu'bricant from said reservoir to said devicesfin substantial excess of the lubricant 'consumption lthereof; a sump beneath saidldevices for'collectfi'ng excess 'lubri'cant therefro'm,v means providing a conduit for returning lubricant from v"said's'iiiri'p torsaid reservoir, filtering kmeans for remo ng solid particles fromvsaid lubricant'beforefi jreturned to vsaid Ireservoir, said filtering'nieans oeingjrelatively smalland of inadequate capacity 'to handle byfigravity said exc'ess delivei'edii'to said Vdevices pumping means ieom'prising a'baring 'sleeve and a spirallygroovedrotary member'vvith'- 'in said sleeve andjarranged'to create a'suct'ion shaft for Vcausing'said Vlubricant to vdrive 'said impeller. v v

d 'vIn arsevving machine, a frame havingfan :enclosed portion providing a lubricant retai'iiing reservoir, a rotary drive shaft extending through said enclosed portion, work feeding devices out- 1side of said reservoir, [connections from said shaft,l for Ioperatir'ig said devices' means for ydelivering lubric'ant 'from said reservoir to fsaid devices in substanti'al excess of thenlubricant consumption thereof, a sump beneath Said-devices for collecting eicess lubricant' therefrbin, means providing a conduit for returningfllubricant from said sump to said reservoir, fitering means for Vremovi'ng solid particlesf from v'said lubricant before,y it is returned to said reservoir, said filtering 'means being relatively smaufaiiii of inadequate capacity to handle by gravitygsaid excess delivered to said devices pumpingmeans comprising a bearing sleeve and a spirally vgrooved rotary 'member Within said a sleeve and arranged -to ycreatea Suction for drawing lubricant through said filtering means,VV and forcing it into said reservoir, and 'connections from-said drive shaft forv Ope-rating saidspirally groroved member i at higher 'angularu Velocity than;-,said shaft, said connections comprising; an impeller connectedwith said member for rotatingJ-the same *and means 4carried lby* said shaft adapted to engage said lubricant -to disperse-the-*same Within said enclosed-:p'ortion of the-frame'for delivery to said :first mentioned 'means and'rto direct ythe' same against saidimpeller to -drive the later. to

y v 7 An cveredge sewing -machine hav-ing- '-aawfrarne with anenclosed portionproviding-a lubricant retaining-reservoir, said framehaving aoeegas a work supporting surface, a rotary drive shaft below said surface and extending through said enclosed portion, a rock shaft connected with said drive shaft within said enclosed portion for oscillation by the latter, said rock shaft extending to a point exterior of said enclosed por- 'tion'above said surface, needle carryingmeans connected with said rock shaft for reciprocation of Vthe needle through said surface, complementary'stitch forming means cooperating with said delivering lubricant from said reservoir to said exterior connections in substantial excess of the lubricant consumption thereof, a sump beneath said surface for collecting excess lubricant supplied to said exterior connections, filtering means mounted in a readily accessible position at the bottom of said sump, said filtering means being relatively small and of inadequate capacity to handle by gravity said excess delivered to said devices, and pumping means connected with said drive shaft and driven thereby for creating a suction beneath said filtering means and drawing ylubricant through said filtering means and returning it to said reservoir.

8. An overedge sewing machine having a frame with an enclosed portion providing a lubricant retaining reservoir, said frame having a work supporting surface, a rotary drive shaft below said surface and extending through said enclosed portion, a rock shaft connected with said drive shaft within said enclosed portion for oscillation by the latter, said rock shaft extending to a point exterior of said enclosed portion above said surface, needle carrying means connected with said rock shaft for reciprocation of the needle through said surface, complementary stitch forming means cooperating with said needle to form overedge stitches, work feeding means beneath said surface exterior of said enclosed portion of the frame, connections from said drive shaft for Operating said complementary stitch forming means and said work feeding means, at least a portion of said connections being exterior of said enclosed portion of the frame, means operated by said drive shaft for delivering lubricant from said reservoir to said exterior connections in substantial excess of the lubricant consumption thereof, a sump'beneath said surface for collecting excess lubricant supplied to said exterior connections, filtering means mounted in a readily accessible position at the bottom of said sump, said filtering means being relatively small and of inadequate capacity to handle by gravity said excess delivered to said devices, a passage communicating with the discharge side of said filtering means and with said reservoir, and a spirally grooved member in said passage driven by said drive shaft for creating a suction beneath said filtering means drawing lubricant through said filtering means and returning it to said reservoir.

9. In a sewing machine, a frame having an enclosed portion providing a lubricant retaining reservoir, a rotary drive shaft extending through said enclosed portion, work feeding devices outside of said reservoir, connections from said shaft for Operating said devices, means forV delivering 16 4 lubricant from said reservoir to said devices 'in substantial excess of the lubricant consumption thereof, a sump beneath said devices for collecting excess lubricant therefrom, filtering means mounted in a readily accessible portion of said frame at the bottom of said sump, said filtering means being relatively small and of inadequate capacity to handle by gravity said excess delivered to. said devices, an enclosed pocket beneath said sump, a cylindrical passage connecting said pocket with said reservoir, a rotary spirally grooved member in said passage and substantially filling the same, and means for rotating said member from said drive shaft, said member and passage being constructed and arranged to provide a suction head on the oil'above the filter upon rotation of said member.

10. In a sewing-machine, a frame having a work supporting surface and anenclosed portion below the level of said surface providing a lubricant reservoir, a rotary drive shaft within said enclosed portion and extending therefrom to a point beneath said work supporting surface, work feeding means beneath said surface exterior of said enclosed portion, connections from said shaft exterior of said enclosed portion for actuating said work feeding means, means fordelivering lubricant from 'said reservoir to said connections upon operation of said shaft in substantial excessof the lubricant consumption of said connections, a sump beneath said connections for collecting excess lubricant therefrom, a pump driven by said shaft for returning lubricant from said sump to said reservoir, said pump comprising a spirally grooved shaft within said reservoir and a bearing sleeve surrounding said shaft, and oil filtering means mounted in a readily accessible portion of said frame between said sump and said pump, said filtering means being relatively small and of inadequate capacityV to handle by gravity said excess delivered to said devices, said pump being constructed and arranged to provide a suction head on the oil above the filter.

11. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a worksupporting surface extending beyond said housing, work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said work'feeding means upon operation of said shaft in substantial excess over the requirements of said work feeding means, a sump beneath said work feeding means for collecting excess lubricant therefrom, filtering means associated with said sump and carried by said frame in a readily accessible position for removing solid particles from the lubricant delivered from said sump, and a pump driven by said shaft connected with the discharge side of said filtering means and arranged to create a suction for drawing lubricant therethrough and returning the same to said reservoir, said pump comprising a spirally grooved shaft portion and a bearing sleeve surrounding said portion, the groove in said shaft portion being of greater width than its' depth.

12. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a work supporting surface extending beyond said housing, work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said work feeding means upon operation of said shaft in substantial excess over the requirements of said work feeding means, a sump beneathsaid work feeding means for collecting excess lubricant therefrom, filtering means associated with said sump and carried by said frame in a readily accessible position for removing solid particles from the lubricant delivered from said sump, and a pump driven by said shaft connected with the discharge side of said filtering means and arranged to create a suotion for drawing lubricant therethrough and returning the same to said reservoir, said pump comprising a spirally grooved shaft portion and a bearing sleeve surrounding said portion, the groove in said shaft portion being about %4 of an inch wide and about 1A; of an inch deep.

13. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a Work supporting surface extending beyond said housing, work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said Vreservoir to said Work feeding means upon operation of said shaft in substantial excess over the requirements of said Work feeding means, a sump beneath said Work feeding means for collecting excess lubricant therefrom, filtering means associated With said sump and carried by said frame in a readily accessible position for removing solid particles from the lubricant delivered from said sump, and a pump driven by said shaft connected with the discharge side of said filtering means and arranged to create a suotion for drawing lubricant therethrough and returning the same to said reservoir, said pump comprising a spirally grooved shaft portion and a hearing sleeve surrounding said portion, the groove in said shaft I portion being of greater width than its' depth,

and having a helix angle about equal to that of a spiral having 8 turns to the inch around a shaft .468 inch in diameter.

14. In a sewing machine, a main driveshaft, a frame having an enclosed housing providing a lubricant reservoir and a Work supporting surface extending beyond said housing, Work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said Work feeding means upon operation of said shaft V in substantial exoess over the requirements of said Work feeding means, a sump beneath said work feeding means for collecting excess lubricant therefrorn, filtering means associated With said sump and carried by said frame in a readily accessible position for removing solid particles from the lubricant delivered from said sump, and a pump driven by said shaft connected With the discharge side of said filtering means and arranged to create a suotion for drawing lubricant therethrough and returning the same to said reservoir, said pump comprising a spirally grooved shaft portion and a bearing sleeve surrounding said portion, said shaft portion having an axial bore, the lubricant being delivered axially into said bore and discharged radially therefrom to the spiral groove in said shaft portion.

15. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a Work supporting surface extending beyond said housing, Work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said.

work feeding means upon operation of said shaft cessible position for removing solid particles from the lubricant delivered from said sump, apurnp driven by said shaft connected With the discharge side of said filtering means and arranged tov create a suotion for drawing lubricant therethrough and -returning the same to said reservoir, said pump comprising a spiraliy grooved shaft connected with said drive shaft and a hearing sleeve surrounding the grooved portion of said grooved shaft, and a stationary member abutting one end of said grooved shaft, said member and said grooved shaft having alined axial passages and spaced radial passages for-the delivery of lubricant from said filtering means to the spiral groove.

16. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a Work supporting surface extending beyond said housing, Work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said Work feeding means upon operation of said shaft in substantial excess over the requirements of said Work feeding means, a sump beneath said Work feeding means for collecting excess lubricant therefrom, filtering means associated With said sump and carried by said frame in a readily accessible position for removing solid particles .from the lubricant delivered from said sump, a pump driven by said shaft connected With the dischargc side of said filtering means and arranged to create a suotion for drawing lubricant therethrough and returning the same to said reservoir, said pump comprising a spirally grooved shaft connected With said drive shaft and a bear-ing sleeve surrounding the grooved portion of said grooved shaft, and a plug,T carried by said sleeve, said plug having a reduced portion abutting the end of said grooved shaft and providing a lubricant receiving pocket in said sleeve communicating With the discharge side of said filtering means, said plug having intercommunioating radial and axial passages, the radial passage communicating with said pocket and the axial passage communicating With a longitudinaliy extending passage in said grooved shaft, said grooved shaft having also a transversely extending passage connecting said longitudinal passage With the grooved surface of said grooved shaft.

17. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a Work supporting surface extending beyond said housing, Work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said Work feeding means upon operation of said shaft in substantial excess over the requirements of said work feeding means, a sump beneath said Work i'eeding means for collecting excess lubricant therefrom, lubricant filtering and pumping means arranged to be applied as a unit to a readily accessible portion of said frame for connecting said surnp With said reservoir, and connections from said drive shaft to said unit for Operating the pumping means, said pumping means being constructed and arranged to provide a suotion head on the oil through the filter.

18. In a sewing machine, a main drive shaft,

a frame having an enclosed housing providing a lubricant reservoir and a work supporting surface extending beyond said housing, Work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant from said reservoir to said Work feeding means upon operation of said shaft in substantial excess over the requirements of said work feeding means, a sump beneath said work feeding means for collecting excess lubricant therefrom, said sump and said reservoir being provided With openings through the bottom walls thereof, closure members inserted in said openings, each of said members having a lubricant receiving pocket, interconnecting means providing a passage for lubricant between said pockets, readily removable filtering means associated With the member in the bottom of said sump, pumping means in the member in the bottom of said reservoir arranged to create a Suction for drawing lubricant through said filtering means and forcing' it into said reservoir, and connections from said drive shaft for Operating said pumping means.

19. In a sewing machine, a main drive shaft, a frame having an enclosed housing providing a lubricant reservoir and a work supporting surface extending beyond said housing, work feeding means beneath said surface exterior of said housing and driven by said shaft, means for supplying lubricant vfrom said reservoir to said Work feeding means upon operation of said shaft in substantial excess over the requirements of said work feeding means, a sump beneath said work feeding means for collecting excess lubricant therefrom, said sump and said reservoir being providedwith openings through the bottom walls thereof, closure members inserted in said openings, each of said members having a lubricant receiving pocket, interconnecting means providing a passage for lubricant between said pockets, readily removable filtering means associated With the'v member in the bottom of said sump, pumping means in the member in the bottom of said reservoir arranged to 'create a suction for drawing lubricant through said filtering means and forcing it into said reservoir, and connections from said vdrive shaft for Operating said pumping means, said members and said interconnecting means being formed as a unit adapted' to be applied in assembled relation to said frame.

' 4 GEORGE SAUER.

CLARENCE C. SMITH.

REFERENCES CITED "I'he following references'are of Vrecord in the file of this patent:

UNITED sTATEs PATENTS Sauer Apr. 4, 1944 

